Non-corrective eyeglasses, such as sunglasses or protective eyeglasses, normally utilize spherical lenses which have substantially the same radius of curvature in both the horizontal and vertical meridians. Such eyeglasses usually do not have sufficient wrap depth to adequately shield the eye from light, wind, and objects at the sides. A large wrap depth is achieved by using lenses which have a sufficiently small radius of curvature to allow the lenses to curve around the sides of the wearer's face. However, spherical lenses having sufficient curvature in the horizontal meridian to provide an adequate wrap depth have an excessive radius of curvature in the vertical meridian, which causes the lenses to project forwardly an excessive distance, thus giving a "bug-eyed" appearance. U.S. Pat. No. 3,526,449, issued to Bolle et al, discloses eyeglasses which use a spherical lens having substantial wrap depth and also use relatively wide temples to shield the wearer's face.
Attempts have been made to provide a lens having sufficient wrap depth without causing the lens to project forwardly an excessive distance, principally by varying the radius of curvature of the lens in the horizontal meridian. Accordingly, the lenses have relatively little curvature at the front, but the curvature increases substantially toward the outer edges of the lenses. An example of this technique is illustrated in U.S. Pat. No. 2,537,047, issued to Gatten. The principal disadvantage of such lenses is the optical distortion caused where the radius of curvature in a horizontal meridian quickly changes. As a result, the optical quality of prior art eyeglasses incorporating this technique has not been particularly great.
Another problem associated with protective eyeglasses adapted for sports use is the inability of the eyeglasses to absorb shocks imparted to the lenses. Conventional eyeglasses generally utilize a nosepiece which is either integrally formed with the lenses or frame or rigidly secured to the frame. As a result, shocks imparted to the lenses by objects are coupled directly to the nose of the wearer, sometimes causing injury.